Viruses infecting humans, animals, plant and insects are well known. Infection of these hosts by viruses can result in disease unless an appropriate immunological response is available to neutralize the infection. Vaccines capable of eliciting the immunological components necessary for an immunological response have been developed to prevent infection by viruses in humans and animals, with notable examples being the flu vaccine and the rabies vaccine, respectively.
Vaccines typically contain an agent that resembles a disease-causing virus. The agent can be a weakened (attenuated) or killed (inactivated) form of the virus. The production of a whole virus vaccine generally begins with the virus being grown either in primary cells (e.g., flu virus) or in continuous cell lines such as cultured human or animal cells (e.g., polio virus). In order to propagate the virus in such cells, the virus must first infect the cells. Accordingly, there is a need for methods of increasing the infectivity of viruses for the making of vaccines.
Viruses also have use in the preparation of viral vectors used by researchers to deliver genetic material into cells and organisms in both a research or gene therapy setting. Such viral vectors are non-naturally occurring viruses. In order to deliver genetic material to a cell, the vectors need to infect a cell. Accordingly, there is a need for viral vectors having increased infectivity to improve the amount of genetic material that can be delivered to target cells or organisms.